• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.4
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• pp.93-99
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• 2022

Analytical solutions for regular waves generated by bottom wave makers in a 3-dimensional wave basin were derived in this study. Bottom wave makers which have triangular, rectangular and combination of two shapes were adopted. The 3-dimensional velocity potential was derived based on the linear wave theory with the bottom moving boundary condition, kinematic and dynamic free surface boundary conditions in a wave basin. Then, analytical solutions of 3-dimensional particle velocities and free surface displacement were derived from the velocity potential. The solutions showed physically valid results for regular waves generated by bottom wave makers in a wave basin. The analytical solution for obliquely propagating wave generation from bottom wave maker which works like a snake was also derived. Numerical results of the solution agree well with theoretically predicted results.

• Korean Institute of Interior Design Journal
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• v.13 no.3
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• pp.145-152
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• 2004

The European architects including MVRDV, Rem Koolhaas, Van Berkel, and Zaha Hadid tend to use the their own design strategy based on the objective data. This Architectural design method leads to make new paradigm of contemporary architecture. For the purpose of the understanding a part of new architecture paradigm I will analyze the case of Villa VPRO designed by MVRDV. At the result, I can draw the following conclusions. First, through collecting and analyzing data, drawing design concept and planning the space program, they decided on the design strategies of Villa VPRO. They designed the space volume having 42.4m$\times$42.4m floors and infiltrated environmental elements to solve the problems about deep space. Second, Villa VPRO was constructed by 'creative space-making system: a series of floors much like a geological formation, the continuous floors interconnected by spatial means, the precision bombardments of snake-like holes, open elevations, the stacking spaces. Third, Villa VPRO produced the spectacle space effect the various formation of continuous floors make a lot of difference space types in this building. Also they lead to move naturally and give event space. A numbers of holes and openness make it possible to provide friendly environment with combining light and air with views of the surrounding and transparency. And using the method of stacking many types of space make the differences in height.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3654-3659
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• 2012

Active contour model or snake is widely used for segmentation method in the area of the image processing and computer vision. The main problem in the active contour model is that results are very dependent to the closet points of the numbers and the location in initial step. Especially, in case of balloon-like active contour model, the small region which consist of intial closet points are expanded until the edge is reached. It is a serious problem because the considered region are huge with limited points. To solve this problem, in this paper, we propose the method that the number of closet points could be change based on the distance between points.

• Journal of Information Processing Systems
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• v.18 no.5
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• pp.688-700
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• 2022

A composite bionic soft gripper integrated with electromagnets and magneto-active elastomers is designed by combining the structure of the human hand and the snake's behavior of enhancing friction by actively adjusting the scales. A silicon-based polymer containing magnetized hard magnetic particles is proposed as a soft finger, and it can be reversibly bent by adjusting the magnetic field. Experiments show that the length, width, and height of rectangular soft fingers and the volume ratio of neodymium-iron-boron have different effects on bending angle. The flexible fingers with 20 vol% are the most efficient, which can bend to 90° when the magnetic field is 22 mT. The flexible gripper with four fingers can pick up 10.51 g of objects at the magnetic field of 105 mT. In addition, this composite bionic soft gripper has excellent magnetron performance, and it can change surface like snakes and operate like human hands. This research may help develop soft devices for magnetic field control and try to provide new solutions for soft grasping.

• The Journal of Korea Robotics Society
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• v.3 no.3
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• pp.203-211
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• 2008

This work proposes structure of spring backbone micro endoscope. For effective surgery in narrow and limited space, many manipulators are developing that different to existed structure. This device can move like elephant nose or snake unlike the existing robots. For this motion, a mechanism that uses spring backbone and wires has been developed. The new type endoscope that has Z axis motion for spring structure, therefore it has 3 degree of freedom, two rotations and one linear motion. And new kinematics for backbone structure is proposed using simple geographic analysis. The Jacobian and stiffness modeling are also derived. Exact actuator sizing is determined using stiffness model. Finally, the proposed kinematics are verified by simulation and experiments.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.219-222
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• 2002

현재 인간처럼 직립 보행을 하거나 강아지처럼 인간과 함께 공존하도록 고안된 다양한 형태의 로봇이 개발되고 있다. 인간에게 보다 친숙한 로봇의 시대가 도래한 것이다. 본 논문에서는 뱀처럼 동작할 수 있는 뱀 형태의 로봇을 구현하고자 한다. 각 모듈은 수직, 수평 이동의 동작을 할 수 있는, 2 DOF를 가지는 모듈을 구성하였다. 여러 개의 모듈의 동작을 동시에 제어 합으로써 뱀의 다양한 동작을 구현하였으며 시각정보의 입력을 받아 물체의 색상과 물체의 형태를 인식할 수 있도록 구현하였다. 각 모듈에서는 2개의 모터 제어기를 내장하고 있으며, 전체 모듈의 제어를 담당하는 중앙처리 장치에서는 실시간 각 모듈의 모터에 동작 신호를 전달하도록 구성하였다. 생물학적으로 관찰한 결과 뱀의 이동은 이동 지점의 환경에 따라 매우 다양하다. 사막에서의 이동과 정글에서의 이동이 다른 형태로 이루어짐을 알 수 있다. 이에, 본 논문에서는 뱀의 다양한 이동 동작을 모방하도록 각 모듈을 제어하였으며, 전체 동작을 관찰하였다. 로봇의 구현 결과 뱀의 이동시 보이는 다양한 동작과 유사한 형태의 동작을 구현할 수 있다

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.279-279
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• 1994

Fibrinolytic proteases, piscivorase I (PI) and piscivorase II (PII), were isolated from Agkistrodon piscivorus piscivorus (eastern cotonmouth moccasin) venom using gel filtration on Bio-Gel P100 and ion-exchange chromatography on CM-Sepharose. The molecular welghts of two proteases were approximately 23400 and 29000. Their isoelectric points 6.6 and 8.5, respectively. The partial amino acid sequences of PI were characterized by tryptic digestion. PI readily cleaves the A${\alpha}$-and B${\beta}$-chaln of fibronogen, but PII rapidly cleaves A${\alpha}$-chain and more slowly the B${\beta}$-chain, They were activated by Ca$\^$2+/, Mg$\^$2+/ and Ba$\^$2+/, but inhibited by Zn$\^$2+/, Cu$\^$2+/ and Mn$\^$2+/. Two enzymes were also inhibited by cysten, ${\beta}$-mercapto -ethanol, and by metal chelators such as EDTA and EGTA, but not by benzamidine, PMSF, soybean trypsin inhibitor and aprotinin. They did not act like thrombin, plasmin and kallikrein, using specific chromogenllc substrates. Two protease did not induce platelet aggregation. PI showed low hemorrhagic activity at dosage of 50 $\mu\textrm{g}$.

• Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.236-239
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• 2009

We describe Ophichthus asakusae from Korea based on a single specimen (426.0 mm TL) collected from the southern sea off Jeju Island. The species is characterized by a pointed, hard, sponge-like tail tip without a caudal fin and 126-132 total vertebrae. We propose a new Korean name, "Je-ju-ba-da-baem" for the species.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.121-123
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• 2009

뱀형 모듈라 로봇은 다양한 환경에 대해서 강인성을 가지고 있고, 모듈 일부의 고장에도 이동할 수 있는 장점을 가진다. 그러나 이동 제어 방법이 어렵고, 아직까지 효율적인 이동법의 개발이 미비한 편이다. 본 연구에서는 뱀형 로봇의 이동제어를 위하여 GA(Genetic Algorithm)기반의 위상제어 방식과 GP(Genetic Programing)를 사용한 임의의 관절궤적 생성 방식을 비교한다. KMC사의 뱀형 로봇을 대상으로 먼저 webots 시뮬레이터 상에서 모델링 및 시뮬레이션을 수행하여 위의 방법들을 비교하였다.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1435-1440
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• 2008

High-speed train under development is a type of EMU(electric multiple units). Since power sources like motors and gears are distributed in the high-speed EMU, the high-speed EMU generates vibration and sound more than the articulated high-speed train. Vibration of vehicle, vibration between rails and wheels, hunting of bogie and snake motion reduce ride comfort. In this paper, to decrease the vibration of the articulated high-speed train, improvements were presented using an analytical model and a simulation model. The simulation model of the high-speed EMU was designed on the basis of the korean high-speed train and the design parameters for ride comfort were showed and the dynamic characteristics of the vehicle was understood. To consider the characteristics of the vehicle suspension, the analytical model was designed and the simulation model was verified with it.